In my existing U.S. Pat. Nos. 3,789,676; 3,857,292; and 4,075,911, it was shown how cycloidal motions, with or without the addition of higher harmonic components, would be generated with simple gear or chain type mechanisms. A common characteristic of all the various mechanisms shown was that the output stroke was equal to the pitch circumference of a gear or sprocket. In the case of linear output systems, the linear output stroke was equal to the pitch circumference of the indexing gear or sprocket; in the case of rotary output systems, the output index angle was equal to the angle subtended by an arc on the output gear or sprocket whose length was equal to the pitch circumference of the eccentric index gear or sprockets. While these systems have been usefully employed in many applications, they are handicapped in generating long strokes by requiring indexing gears or sprockets which become impractically large.
It is one object of the present invention to provide an indexing system which is capable of generating an accelerated-decelerated index stroke during multiple revolutions of the index gear; accordingly, a proportionally smaller gear can be employed.
In such a multiple revolution gear index system, the natural dwell between the index strokes will become smaller as related to the input angle than is that same natural dwell for a single revolution index system.
It is another object of this invention to provide an indexing system in which the dwell between index strokes can be significantly extended and thereby to provide ample time for stoppage or reversal of the driving motor.
In a conventional cycloidal indexing system, the peak velocity reached at or near midstroke is approximately two times the average velocity during the stroke.
It is another object of this invention to provide an indexing system in which the peak velocity reached during the stroke is significantly less than two times the average velocity reached during the stroke.
Other objects and features of the invention will be apparent in the following description and claims in which the principles of the invention are set forth together with details of the structure which will enable a machine builder to utilize the invention, all in connection with the best modes presently contemplated for the practice of the invention.